UPSC Prelims S.E.E. Snapshot: MIRV Technology, Exchange rate and AMOC

SCIENCE

MIRV Technology 

Core Concept: 

— MIRV technology is the capability that allows multiple warheads to be loaded on a single missile delivery system and programmed to hit different targets, thus greatly enhancing the missile’s destructive potential. 

— Traditional missiles carry a single warhead, or weapon, that goes and hits the intended target. MIRV-equipped missiles can accommodate multiple warheads, each of which can be programmed to strike a separate target. They can all be made to hit the same location too, one after the other, thus ensuring complete annihilation of the target.

— Notably, it is a complicated technology. The warheads have to be miniaturised, be equipped with independent guidance and navigation controls, and released sequentially from the delivery system. 

📍Key features of MIRV technology

— Inflicting serious damages: With simultaneous targeted strikes at a single or multiple locations, MIRV-equipped missiles are capable of inflicting catastrophic damages. 

— Launch counterattack: The ability to launch a counterattack with the potential to do enormous damage is another significant strategic benefit. If the counterattack is too strong, the opposition can be discouraged from assaulting.

— Difficult to intercept: MIRV-equipped missiles can render the missile defence system useless.  Multiple warheads, each with an independent trajectory, can make the job of tracking and intercepting extremely complicated.

— Ability to penetrate missile defence systems: It is possible to modify MIRV-equipped missiles to carry dummy warheads, which would trick the defence system. It is therefore quite likely that one or more warheads will breach the defence shield and cause significant damages.

— Use of high-precision sensor and avionics systems: The technology has made substantial advances such as using high-precision sensor packages and indigenously avionics systems to guarantee that the re-entry vehicles reach the target points with the required accuracy.

📍UPSC Twist Point– MIRV vs MaRV (Maneuverable Re-entry Vehicle) 

— The MaRV is a type of ballistic missile warhead capable of maneuvering and changing its trajectory during the terminal phase of flight, unlike traditional ballistic missiles that follow a predictable, arc-like path.  

— MaRV enables maneuvering during atmospheric re-entry. It enhances missile survivability against anti-ballistic missile (ABM) systems. 

ECONOMY

Exchange rate

Core Concept:

— The rate at which one can swap between currencies is the exchange rate. In other words, how many rupees would buy you a dollar or a euro.

— In the currency market each currency is like a commodity itself. The value of each currency relative to another currency is called the exchange rate.

— The rupee’s exchange rate vis-a-vis a particular currency, say the US dollar, tells us how many rupees are required to buy a US dollar. To buy (import) a US product or service, Indians need to first buy the dollars and then use those dollars to buy the product. The same holds true for Americans buying something from India.

— If the rupee’s exchange rate “falls”, it implies that buying American goods would become costlier. At the same time, Indian exporters may benefit because their goods now are more attractive (read cheaper) to the American customers.

— In a free-market economy, the exchange rate is decided by the supply and demand for rupees and dollars.

— Imagine that in the beginning, one rupee was equal to one dollar. After a year, Indians demand more dollars in comparison to Americans demanding the rupee. In such a case, the exchange rate will “fall” or “weaken” for rupee and “rise” or “strengthen” for dollar.

— However, in India, the exchange rate is not fully determined by the market. From time to time, the RBI intervenes in the foreign exchange (forex) market to ensure that the rupee “price” does not fluctuate too much or that it doesn’t rise or fall too much all at once.

📍UPSC Twist Points– Exchange rates vs Forex reserves (Forex)

— Foreign exchange reserves are an important component of the Balance of Payment (BoP) and an essential element in the analysis of an economy’s external position. In times of crisis, adequate foreign exchange reserves give comfort, acting as a buffer and giving strength to a country’s macroeconomic fundamentals. 

— The RBI has the primary responsibility of collection, compilation and dissemination of data relating to foreign exchange reserves.

— India’s foreign exchange reserves comprise foreign currency assets (FCA), gold, special drawing rights (SDRs) and reserve tranche position (RTP) in the International Monetary Fund (IMF). 

ENVIRONMENT

Atlantic Meridional Overturning Circulation 

Core Concept:

— Think of the Earth’s oceans as having a massive, invisible conveyor belt. In the Atlantic Ocean, this system is scientifically known as the Atlantic Meridional Overturning Circulation. 

— The AMOC is a large system of ocean currents. It is the Atlantic branch of the ocean conveyor belt or thermohaline circulation (THC), and it distributes heat and nutrients throughout the world’s ocean basins.

— AMOC carries warm surface waters from the tropics towards the Northern Hemisphere. As it reaches the freezing Arctic, the water cools, becomes denser, and sinks several kilometres into the deep ocean. It then drifts back south as a cold deep-water current before eventually rising to the surface to warm up and restart the loop. This slow machinery moves vast amounts of heat across the globe.

— The conveyor belt relies on a delicate balance of ocean temperature and salt levels. However, human-induced climate change is melting Arctic ice at an alarming rate, dumping massive amounts of fresh water into the North Atlantic. Because fresh water is lighter and less salty, it does not sink easily. This is acting like a brake on the entire AMOC system. 

— While past studies estimated a 15% slowdown over the last 50 years, new research using real-time ocean measurements projects a much sharper decline, potentially weakening the currents by up to 59% by 2100.

— This matters because the AMOC is a “climate tipping point”. Just like a chair tilted past its balancing point, once the AMOC crosses a certain threshold, it could irreversibly collapse into a new, sluggish state. If it does, the consequences would be catastrophic, triggering extreme sea-level rise in North America and severe weather disruptions globally.

— Notably, though the AMOC is in the Atlantic, its breakdown would trigger chaos in the Pacific. 

— El Niño is a periodic warming of the Pacific Ocean that disrupts global weather. Because global ocean currents and wind patterns are deeply interconnected, a sluggish AMOC traps heat in the southern hemisphere and leaves the North Pacific cooler.

— Studies suggest a weaker AMOC will make El Niño events more unpredictable and extreme.  

📍UPSC Twist Points– AMOC  Vs  El Niño South Oscillation (ENSO)

— The El Niño Southern Oscillation (ENSO) is a climate phenomenon marked by changes in sea temperatures along the eastern Pacific Ocean, coupled with fluctuations in the overlying atmosphere. It can alter and interfere with the global atmospheric circulation, which, in turn, influences the weather worldwide.

— It has three phases: warm (El Niño), cool (La Niña), and neutral. It occurs in irregular cycles of 2 to 7 years. 

Prelims Practice MCQ

Let’s see how much can you recall

Consider the following statements:

1. MIRV technology enables a single ballistic missile to carry multiple independently targetable warheads capable of striking different locations.

2. In a freely floating exchange rate system, the value of a currency is determined by demand and supply in the foreign exchange market.

3. The Atlantic Meridional Overturning Circulation (AMOC) is primarily driven by wind patterns and is independent of differences in ocean temperature and salinity.

How many of the statements given above is/are correct?

(a) Only one

(b) Only two

(c) All three

(d) None

ALSO CHECK

UPSC Prelims S.E.E. Snapshot: GPS interference, RBI’s Monetary Policy, Heatwaves

UPSC Prelims S.E.E. Snapshot: Dimethyl Ether, CPI overhaul, Tar Balls 

UPSC Prelims ‘SEE’ Snapshot : Induction cooktop, Forex reserve, and Earth’s energy imbalance 

UPSC Prelims ‘SEE’ Snapshot: Talking cars, GDP rebasing and Nor’westers — quick look 

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